Gardai fear dissident Republican reprisal attacks after a Real IRA commander was shot dead in Cork.
Aidan O'Driscoll (37), nicknamed 'The Beast', died during emergency surgery just over an hour after being shot three times in an ambush style attack in Blackpool.
Just three years ago the Ballyvolane native had survived another gun attack.
Mr O'Driscoll was shot in the legs during a 2013 Cork attack after what Gardaí believed was a punishment operation carried out by fellow dissident Republicans.
At one point, he was suspected to have served as chief of staff for the Real IRA in Munster.
The fatal shooting took place in a quiet residential area.
He was shot outside an apartment complex off the Commons Road in Blackpool in Cork, not far from a local church.
The attack took place shortly before 5pm and is understood to have involved a lone gunman and an accomplice who acted as a getaway driver.
Locals reported hearing several loud bangs and seeing a man, apparently masked, running from the scene.
He is then believed to have fled the area in a waiting car driven by another man.
Initial reports are that Mr O'Driscoll realised he was being ambushed and attempted to flee, only to be shot in the back with a handgun.
He was then shot a number of times as he lay wounded on the pavement.
A vehicle was later found a short distance away, close to the North Monastery, having been set on fire.
Mr O'Driscoll was treated at the scene by paramedics before being rushed to Cork University Hospital (CUH).
It is understood he suffered at least three gunshot wounds to the back.
He died while undergoing emergency surgery at CUH.
Mr O'Driscoll was convicted before the Special Criminal Court in 2005 of being a member of the Real IRA.
He received a three year prison sentence for being a member of the dissident group on December 13 2003.
Four other men were also convicted of Real IRA membership in a combined trial.
However, Mr O'Driscoll's conviction was subsequently overturned by the Court of Criminal Appeal in May 2008.
The court quashed the convictions on the basis the Special Criminal Court did not have jurisdiction in the matter because the men were not charged "forthwith."
Mr O'Driscoll was the only one of the five who had been in custody.
During the 2005 trial, a senior garda gave evidence that Mr O'Driscoll was part of a feared active service unit of the Real IRA in Munster.
It was also believed Mr O'Driscoll had been closely allied to Alan Ryan who was shot and killed in Dublin in 2012.
On Wednesday night, Gardaí sealed off the scene in Blackpool to allow for a detailed investigation by forensic experts.
Officers also began door-to-door inquiries in the area to determine if anyone witnessed anything suspicious or may have seen the gunman as he fled the scene.
Gardai stressed that they are keeping an open mind as to the possible motive for the attack.
However, the primary theories are that it was either a revenge attack against Mr O'Driscoll linked to an earlier feud or part of a deadly escalation in a turf war within the dissident Republican ranks.
Gardai are appealing for witnesses and anyone with information, particularly those who may have been in the vicinity of Great William O’Brien Street and or The Church of the Annunciation, Blackpool on Wednesday between the hours of 3.30pm and 5.30pm to contact them at Mayfield Garda Station on 021 4558510, The Garda Confidential Line 1800 666111 or any Garda Station.